Adrodd fel Amhriodol

' Filter beds went out of use sometime in the late 70s or early 80s as water is no longer used directly from the reservoir. '

Dywedwch wrthym pam mae’r cynnwys hwn yn amhriodol *(gofynnol)

Dewis categori *(gofynnol)

Os ‘Arall’ rhowch fanylion (dewisol)

Eich enw (dewisol)

Eich cyfeiriad e-bost (dewisol)

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